The invention relates to a mash copper (or mash tun) having a body of circular cross-section and a tun bottom inclined to the centre and constructed as a heating surface.
Mash coppers having a circular cross-section and a conical or uniformly arched heating bottom are known. In such mash coppers the mixing of the mash and the heat transfer are not optimal. The mash is moved with a pushing motion in the copper, the mash particles preferably moving in horizontal planes. To obtain, in spite of this, a sufficient mixing and an improved heat transfer flow breakers must generally be installed and in addition a relatively high speed of rotation of the agitator must be used. However, high peripheral speeds of the stirrer or agitator have technological disadvantages because there is a danger of damage to the glume particles both at the sharp-edged parts of the agitator and of the flow breakers.
Furthermore, mash coppers having a rectangular cross-section also are known. In such mash coppers, although a more pronounced upward movement of the mash particles and thus an improved mixing is obtained, in the vicinity of the (usually rounded) corners of the vessel a pulsating stirring action results and thus an irregular heat transfer. Also disadvantageous is the large peripheral speed of the agitators required in mash coppers with rectangular cross-section and the relatively high energy consumption.